USS Albacore (AGSS-569)

USS Albacore (AGSS-569) is a retired United States Navy research submarine, the only one of its kind, built to test a new hull shape for undersea warfare. Its keel was laid down at the Portsmouth Naval Shipyard in Kittery, Maine, in March 1952, and it was launched in August 1953 and commissioned that December. The Navy designed it for speed and agility underwater rather than for combat, after hydrodynamic studies at the David Taylor Model Basin and wind tunnel tests, and its teardrop form, often called the Albacore hull, became the basis for the hulls of modern American submarines. Through the 1950s and 1960s it was repeatedly rebuilt to try different tails, propellers, control surfaces and batteries. It ran on General Motors EMD 16-338 pancake diesel engines, whose frequent failures and lack of spare parts led to its decommissioning in 1972. It is now a museum ship at Albacore Park in Portsmouth, New Hampshire, and a National Historic Landmark.